To meet customer demands for safety, security and convenience, many vehicles such as automobiles are increasingly becoming available with the capability to make “hands free” cellular/wireless telephone calls using a vehicle audio system. Such systems typically use the vehicle audio speakers to play telephone audio, and use a microphone to pick up voices in the passenger cabin, thereby leaving the driver's hands free to maneuver the vehicle. One type of vehicle telephony system is the ONSTAR service available from General Motors Corporation, which provides a telephony system that is built into the vehicle at the factory. ONSTAR telephony can be used to safely make telephone calls, to obtain emergency assistance, and/or to obtain directions or other information while the vehicle is in operation.
Although on-board telephone systems such as the ONSTAR system have proven to be quite useful and convenient, many drivers and passengers nowadays carry their own personal wireless phones even when they are away from their vehicles. For many users, the portable wireless phone is a primary mode of contact, thereby requiring the user to have access to the phone at all times, including when the user is operating or riding in a vehicle. If a user receives a call on a wireless phone while driving, however, that person may focus his or her attention on using the phone for the duration of the call, thereby resulting in reduced attention to operating the vehicle. Moreover, if a person receives a call on one phone (e.g., a portable wireless phone) while talking on a call received or placed via another phone (e.g., the onboard telephony system), even more distraction can take place as the user either attempts to handle both calls simultaneously or ignores one of the calls while processing the other manually. This problem is worsened if multiple passengers are riding in the vehicle, each with their own portable phones.
More recently, techniques have been developed that allow users to answer and originate telephone calls using their personal handheld phones through the vehicle's audio system. Although these systems allow wireless calls to be handled in a “hands free” manner without distracting the driver, typically only one phone is allowed access to the vehicle audio system at any time.
Accordingly, it is desirable to create a technique that allows multiple phones to share access to the vehicle audio system. In addition, it is desirable to create a vehicle audio system capable of safely processing multiple simultaneous calls via multiple telephones. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.